1. Field of the Invention
The present invention relates to a semiconductor storage circuit of the type in which a plurality of storage elements are provided with storage capacitors and are grouped in rows and columns and integrated on a doped semiconductor body, wherein the storage elements which, in each case, form a row are provided with a common first drive line, the storage elements which, in each case, form a column are provided with a common second drive line, the first drive lines are formed from strip-like electrically conductive layers which are separated by an insulating layer from the surface of the semiconductor body, the second drive lines consist of buried lines which extend inside the semiconductor body and are oppositely doped with respect to the semiconductor body, the insulating layer is designed to be thinner inside the intersection zones of the drive lines than outside thereof, and that in these zones insulating capacitors are formed which possess outer electrodes composed of parts of the first drive lines and which represent storage capacitors of the storage elements. More particularly, the width of the buried lines which represent the second drive lines is designed to be less than the dimensions, oriented transversely to these strips, of the aforementioned other electrodes, and that between the buried lines which represent the second drive lines further buried lines are arranged which can be connected by way of terminals to a voltage source.
2. Description of the Prior Art
A storage circuit of the type generally mentioned above is described in detail in the IEEE Journal of Solid-State Circuits, Vol. SC-12, No. 5, October 1977, pp. 534-536. In this storage circuit, the first drive lines are referred to as word lines, the second drive lines are referred to as buried collectors or bit lines, and the insulating layer capacitors are referred to as metal-oxide-semiconductor (MOS) capacitors. The German patent application No. P 27,43948.1 also describes a storage circuit of this type in detail.
When a recorded item of binary information is read from one of the storage elements, the two drive lines assigned to the element are connected to voltages which are such that the minority charge carriers stored in the insulating layer capacitor are injected into the semiconductor body and collected by the second drive line or buried collector. Here, a change occurs in the state of charge of the space charge capacitance of the second drive line which, for this purpose, is released from external potentials, i.e. occupies a "floating" state. While leaving other conditions unchanged, the change in charge leads to a read-out signal on the second drive line which is the greater in magnitude the smaller the quotient of the aforementioned space charge capacitance and the capacitance of the insulating layer capacitor.